tomoyuki-nakabayashi
commented
6 years ago #include <stdint.h>
/* UART0 address on riscv-qemu 'virt' machine */
volatile uint8_t *uart16550 = (uint8_t *)0x10000000;
volatile uint32_t *testfinisher = (uint32_t *)0x100000;
enum {
UART_REG_QUEUE = 0,
UART_REG_LINESTAT = 5,
UART_REG_STATUS_RX = 0x01,
UART_REG_STATUS_TX = 0x20
};
static inline void display_string(uint8_t string){
while((uart16550[UART_REG_LINESTAT] & UART_REG_STATUS_TX) == 0);
uart16550[UART_REG_QUEUE] = string;
}
int main(){
char* str = "hello world\n";
while (*str != '\0') {
display_string(*str);
str++;
}
*testfinisher = 0x5555;
return 0;
}80000000 <reset_vector>:
80000000: 0040006f j 80000004 <do_reset>
80000004 <do_reset>:
80000004: 00000093 li ra,0
80000008: 00000113 li sp,0
8000000c: 00000193 li gp,0
80000010: 00000213 li tp,0
80000014: 00000293 li t0,0
80000018: 00000313 li t1,0
8000001c: 00000393 li t2,0
80000020: 00000413 li s0,0
80000024: 00000493 li s1,0
80000028: 00000513 li a0,0
8000002c: 00000593 li a1,0
80000030: 00000613 li a2,0
80000034: 00000693 li a3,0
80000038: 00000713 li a4,0
8000003c: 00000793 li a5,0
80000040: 00000813 li a6,0
80000044: 00000893 li a7,0
80000048: 00000913 li s2,0
8000004c: 00000993 li s3,0
80000050: 00000a13 li s4,0
80000054: 00000a93 li s5,0
80000058: 00000b13 li s6,0
8000005c: 00000b93 li s7,0
80000060: 00000c13 li s8,0
80000064: 00000c93 li s9,0
80000068: 00000d13 li s10,0
8000006c: 00000d93 li s11,0
80000070: 00000e13 li t3,0
80000074: 00000e93 li t4,0
80000078: 00000f13 li t5,0
8000007c: 00000f93 li t6,0
80000080: 34001073 csrw mscratch,zero
80000084: 00002117 auipc sp,0x2
80000088: efc10113 addi sp,sp,-260 # 80001f80 <stacks+0xf80>
8000008c: 05c000ef jal ra,800000e8 <main>
80000090: 10500073 wfi
80000094 <display_string>:
80000094: fe010113 addi sp,sp,-32
80000098: 00812e23 sw s0,28(sp)
8000009c: 02010413 addi s0,sp,32
800000a0: 00050793 mv a5,a0
800000a4: fef407a3 sb a5,-17(s0)
800000a8: 00000013 nop
800000ac: 800007b7 lui a5,0x80000
800000b0: 16c7a783 lw a5,364(a5) # 8000016c <pulp__FC+0x8000016d>
800000b4: 00578793 addi a5,a5,5
800000b8: 0007c783 lbu a5,0(a5)
800000bc: 0ff7f793 andi a5,a5,255
800000c0: 0207f793 andi a5,a5,32
800000c4: fe0784e3 beqz a5,800000ac <display_string+0x18>
800000c8: 800007b7 lui a5,0x80000
800000cc: 16c7a783 lw a5,364(a5) # 8000016c <pulp__FC+0x8000016d>
800000d0: fef44703 lbu a4,-17(s0)
800000d4: 00e78023 sb a4,0(a5)
800000d8: 00000013 nop
800000dc: 01c12403 lw s0,28(sp)
800000e0: 02010113 addi sp,sp,32
800000e4: 00008067 ret
800000e8 <main>:
800000e8: fe010113 addi sp,sp,-32
800000ec: 00112e23 sw ra,28(sp)
800000f0: 00812c23 sw s0,24(sp)
800000f4: 02010413 addi s0,sp,32
800000f8: 800007b7 lui a5,0x80000
800000fc: 15c78793 addi a5,a5,348 # 8000015c <pulp__FC+0x8000015d>
80000100: fef42623 sw a5,-20(s0)
80000104: 0200006f j 80000124 <main+0x3c>
80000108: fec42783 lw a5,-20(s0)
8000010c: 0007c783 lbu a5,0(a5)
80000110: 00078513 mv a0,a5
80000114: f81ff0ef jal ra,80000094 <display_string>
80000118: fec42783 lw a5,-20(s0)
8000011c: 00178793 addi a5,a5,1
80000120: fef42623 sw a5,-20(s0)
80000124: fec42783 lw a5,-20(s0)
80000128: 0007c783 lbu a5,0(a5)
8000012c: fc079ee3 bnez a5,80000108 <main+0x20>
80000130: 800007b7 lui a5,0x80000
80000134: 1707a783 lw a5,368(a5) # 80000170 <pulp__FC+0x80000171>
80000138: 00005737 lui a4,0x5
8000013c: 55570713 addi a4,a4,1365 # 5555 <reset_vector-0x7fffaaab>
80000140: 00e7a023 sw a4,0(a5)
80000144: 00000793 li a5,0
80000148: 00078513 mv a0,a5
8000014c: 01c12083 lw ra,28(sp)
80000150: 01812403 lw s0,24(sp)
80000154: 02010113 addi sp,sp,32
80000158: 00008067 ret
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